Tailoring Interfacial Physicochemical Properties in Cu₂O-TiO₂@rGO Heterojunction: Insights from EXAFS and Electron Trap Distribution Analysis

Abstract

In this study, a solution-based synthesis technique was utilized to produce Cu 2 O nanoparticles (NPs) on TiO 2 nanofibers (TNF), which were then subsequently coated with reduced graphene oxide (rGO) nanosheets. In the absence of any cocatalyst, CTNF@rGO-3% composite displayed an ideal photocatalytic H 2 evolution rate of 96 μmol g −1 h −1 under visible light irradiation, this was 10 times higher than that of pure TNF. At 420 nm, the apparent quantum efficiency of this composite reached a maximum of 7.18%. Kelvin probe force microscopy demonstrated the formation of an interfacial electric field that was oriented from CTNF to rGO and served as the driving force for interfacial electron transfer. The successful establishment of an intimate interface between CTNF@rGO facilitated the efficient transfer of charges and suppressed the rate of recombination of photogenerated electron−hole pairs, leading to a substantial enhancement in photocatalytic performance. X-ray photoelectron spectroscopy, photoluminescence spectra, and electrochemical characterization provide further confirmation that formation of a heterojunction between CTNF@rGO leads to an extension in the lifetimes of the photogenerated charge carriers. The experimental evidence suggests that a p−n heterojunction is the mechanism responsible for the significant photocatalytic activity observed in the CTNF@ rGO composite during H 2 evolution.

Improved Performance of QDSSCs Can Be Achieved by Constructing a Transparent Anatase TiO2@MWCNT Photoanode Based on the Bionic Mountain Lotus

“…Figure a–c presents the total XPS spectrum, O 1s spectrum, and Ti 2p spectrum of the A TiO 2 NPs thin film material, respectively Figures d–f display the total XPS spectrum, O 1s spectrum, and Ti 2p spectrum of the TA TiO 2 thin film material, respectively. , Figure g–i depict the total XPS spectrum, O 1s spectrum, and the Ti 2p spectrum of the TA TiO 2 @MWCNT thin film material, respectively. Comparative analysis reveals that the oxidation states of the O and Y elements in the prepared TA TiO 2 , TA TiO 2 @MWCNT, and A TiO 2 NPs are essentially identical.…”

“…The improvement in battery performance is primarily attributed to the enhancement in J sc resulting from the increase in surface morphology. Although the specific surface area of TA TiO 2 @MWCNT film is still lower than that of A TiO 2 NPs film, during the operation of the battery, excess charge carriers are in a quasi-equilibrium state. , The excess charge carriers are generated by optical excitation, causing the rate of carrier generation to exceed the recombination rate. Excess charge carriers typically decay exponentially: normalΔ n ( t ) = false( normalΔ n false) 0 e − t / τ …”

“…The improvement in battery performance is primarily attributed to the enhancement in J sc resulting from the increase in surface morphology. Although the specific surface area of TA TiO 2 @MWCNT film is still lower than that of A TiO 2 NPs film, during the operation of the battery, excess charge carriers are in a quasi-equilibrium state. , The excess charge carriers are generated by optical excitation, causing the rate of carrier generation to exceed the recombination rate. Excess charge carriers typically decay exponentially: …”

Exploring the Potential of Copper Palladium Nanocube Electrocatalysts for Enhancing the Overall Water Splitting Performance

“…35−38 The core level Cu 2p spectra (Figure 3c), the binding energy at 934. 16 We have also studied the XPS analysis for Cu 2 O 39,40 and PdO 41,42 , as seen in Figures S4 and S5.…”

“…The deconvoluted O 1s spectra (Figure d) at binding energies of 529, 530, and 531 eV correspond to M–O, M–O–M, and M–OH, clearly confirms the formation of CuPd catalyst. We have also studied the XPS analysis for Cu 2 O , and PdO , , as seen in Figures S4 and S5.…”